Modern biotechnology stems from the recombinant DNA technology of the 1970s, but the discipline has grown far beyond that core. The people, products, and potentials of biotechnology have mushroomed from a handful of companies focused on a select few pharmaceuticals to hundreds of firms developing products for such diverse fields as forensics, food science, and environmental cleanup. Today, biotech consumers range from megacorporations to a couple at home confirming that a child is on the way.

Molecular biology has come a long way in the nearly 40 years since James Watson and Francis Crick published their classic paper on the three-dimensional structure of DNA (Nature, 171:737-738, 1953). Since then, the intimate relationship between nucleic acids and proteins has not only been deciphered, but also harnessed and manipulated to fuel a whole new industry. Armed with sophisticated equipment, today's molecular biologists can easily extract, purify, and sequence DNA, RNA, and proteins, a

In 1949, a team led by chemist Linus Pauling placed hemoglobin solutions from people with a disabling form of anemia and from healthy volunteers in an electric field, and found that the two samples migrated at different rates. In this way, the technique of electrophoresis helped decipher the molecular abnormality behind sickle cell disease, the most common genetic disease among blacks. Forty years and many modifications later, a variation of the same technique helped highlight the differences

Many biochemical studies routinely performed by researchers, such as protein assays and DNA studies, require the detection of extremely minute quantities of material. However, such small quantities are usually undetectable by the Lowry assay, UV spectroscopy, and other conventional methods of chemical analysis. This problem was solved with the development in the 1940s of chemical tests that use radioisotopes to label the material in question before it is assayed. This technology has allowed sci

Most life scientists, at some point in their careers, are faced with the problem of purifying a specific protein from a biological solution. For example, they may need to purify an antibody from a serum, or a single E. coli protein from an extract. The separation of a single protein from a mixture of thousands is a considerable task - it takes a long time to collect enough raw materials to make purification worthwhile. Purification is necessary, however, to provide valuable information about th

For many years, geneticists determined the genetic makeup of organisms by examining the physical characteristics of their offspring. But with the discovery of the structure of the DNA double helix, first published by James D. Watson and Francis H.C. Crick in 1953 (Nature, 171:964-7), the science of genetics was forever changed. Scientists soon developed techniques to study the genetic message found in all living cells at the molecular level. One of most important of these methods was the use of

One of the most important advances in the field of cell biology came in the early 20th century, with the discovery that plant and animal cells could survive - and even replicate - outside the living organism. In 1907, R.G. Harrison, a neurobiologist trying to prove that nerve fibers were actually outgrowths of single cells, chopped up spinal cord tissue and added it to clotted plasma in a humidified growth chamber. The nerve cells from this crude explant not only grew and divided in this enviro